Just moved into a new house in San Diego. Sprinklers had been watering the lawn for an hour and a half every day for who knows how long. Any idea what this black stuff is?
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nilesandstuff
Mold, moss, algae. Something along those lines. I see it often in extremely waterlogged areas, never really bothered to pin point exactly what it is (and it might not always be the same thing every time)… But it’s certainly no bueno.
Making it not be so wet all the time is likely all that’s needed to address it. If you’re really angry at it, spraying it with hydrogen peroxide would kill it (though it’ll just return if the area stays wet)
The hydrogen peroxide solution would be 3-5 parts water to 1 part 3% hydrogen peroxide.
Dilluted hydrogen peroxide won’t hurt grass, infact, grass would really like it… When it reacts with essentially anything, it releases a lot of oxygen, which grass roots love.
raptorsympathizer
I’m massively struggling with this in our yard. To the best of my knowledge, it’s moss or algae. We have extremely heavy clay soil and partial shade — so it’s unfortunately ideal conditions for this to thrive.
MillionBagger
Ash from LA.
Any1fortens
The black stuff is the result of anaorobic soil. Caused by lack of water or poor drainage, which inhibits the flow of oxygen. Get the carbon dioxide out of your soil and allow the oxygen to get into your soil. A simple process known as aerification.
Forget adding chemicals until you have done that a few times. Or more!
howfastwasigoing
It’s dead weed residue. Some temperature or hours of sunlight sensitive weed
6 Comments
If you’re asking for help with identifying a weed and/or type of grass, please include close-up photos showing as much detail as possible.
For grasses, it is especially important to get close photos from multiple angles. It is rarely possible to identify a grass from more than a few inches away. In order to get accurate identifications, the more features of the grass you show the more likely you are to get an accurate identification. Features such as, [ligules](https://extension.illinois.edu/sites/default/files/styles/image_gallery_mobile/public/2024-03/180.png.jpg?itok=D5yNs0l8) (which can be hairy, absent entirely, or membranous (papery) like the photo), [auricles](https://extension.illinois.edu/sites/default/files/styles/image_gallery_mobile/public/2024-03/Grasses%20at%20a%20Glance%20Blog%20Pictures.png.jpg?itok=PLrWX4q-), any hairs present, roots, stems, and any present seed heads. General location can also be helpful.
Pull ONE shopt and get pictures of that.
[This page from MSU](https://www.canr.msu.edu/news/grass-photography-tips-for-id-help-us-help-you) has helpful tips on how to take pictures of grasses for the purposes of identification.
u/nilesandstuff
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Mold, moss, algae. Something along those lines. I see it often in extremely waterlogged areas, never really bothered to pin point exactly what it is (and it might not always be the same thing every time)… But it’s certainly no bueno.
Making it not be so wet all the time is likely all that’s needed to address it. If you’re really angry at it, spraying it with hydrogen peroxide would kill it (though it’ll just return if the area stays wet)
The hydrogen peroxide solution would be 3-5 parts water to 1 part 3% hydrogen peroxide.
Dilluted hydrogen peroxide won’t hurt grass, infact, grass would really like it… When it reacts with essentially anything, it releases a lot of oxygen, which grass roots love.
I’m massively struggling with this in our yard. To the best of my knowledge, it’s moss or algae. We have extremely heavy clay soil and partial shade — so it’s unfortunately ideal conditions for this to thrive.
Ash from LA.
The black stuff is the result of anaorobic soil. Caused by lack of water or poor drainage, which inhibits the flow of oxygen. Get the carbon dioxide out of your soil and allow the oxygen to get into your soil. A simple process known as aerification.
Forget adding chemicals until you have done that a few times. Or more!
It’s dead weed residue. Some temperature or hours of sunlight sensitive weed